Today, the modern consumer of bread products is looking constantly for high quality products. Besides freshness, shape and other characteristics, aroma and taste are of particular importance when making the choice for buying bread.
Sourdough fermentations and sourdough products addition to doughs are among other well known techniques to improve the aroma and the taste of breads. Typical tastes/aromas given by sourdough are lactic, acetic, toasted, fruity, fermented or cereal. Sourdoughs are generally obtained by the fermentation of cereals or cereal flours by strains of lactic acid bacteria and/or baker's yeast. Lactic acid bacteria isolated from sourdoughs are mainly Lactobacillus, Leuconostoc, Pediococcus and Streptococcus, but the majority belongs to the Lactobacillus group. Lactic acid bacteria fermentation generates lactic acid and/or acetic acid that give the acidity to the sourdough. Saccharomyces cerevisiae is the most frequent yeast species in conventional sourdough. Other species of Saccharomyces, Candida, Pichia and Hansenula have occasionally been isolated and used. It is generally considered that in sourdoughs, the ratio of lactic acid bacteria number to yeast number should be over 100 for optimal activity.
Three types of sourdoughs are generally recognized:                Traditional sourdoughs: sourdoughs that are restarted using a part of the previous fermented dough which is therefore constantly renewed in a cyclical way, using specific recipes and ripening conditions. The mother dough is then mixed with rest of the flour, water, salt and fat to a suitable consistency, and then given a short period for fermentation before final proving and baking.        Active sourdoughs: improved type of sourdoughs using adapted strains or liquid sourdough starters to start the fermentation. These sourdoughs can be pasty or liquid and are generally stable and easy to process for example in an automated bakery. There are enough living lactic acid bacteria and/or yeast to ferment a bread dough successfully or to initiate a multiple stage sourdough process.        Inactive powder or liquid sourdoughs: used by traditional or industrial bakeries for their convenience since the quality is constant and they are easy to use. They will deliver the acidity and the conventional sourdough flavor directly avoiding a long fermentation step.        
In the prior art it is known to use other microbial strains than baker's yeast or lactic acid bacteria during bread dough fermentation. JP2001204376 describes the use of combinations of Lactobacillus and acetic acid bacteria such as Acetobacter and Gluconobacter together with yeast to prepare wheat flour doughs. Doughs made this way show improved properties and especially an increased volume of the dough, thereby obtaining high quality bread excellent in an outward appearance.
EP0903082 describes the use of mixtures of Lactobacillus and Gluconobacter strains (and eventually Saccharomyces chevalieri) to obtain a liquid ferment that reproduces the aroma of bagels. JP10201495 describes the use of a mixed culture of a cellulose producing bacterium (e.g. Acetobacter xylinum subsp. sucrofermentans) and another microorganism (a Lactobacillus, a yeast, etc.) to produce a cellulosic substance that can be used for strengthening food material doughs.
It is the aim of the present invention to provide breads with a constant quality, and with a new typical aroma and taste. Accordingly there is a need to have new stable ingredients as well as methods to obtain these ingredients.